package com.eric.springboot.config.security;

import com.eric.springboot.utils.JwtTokenUtil;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * JWT登录授权过滤器
 *
 * @author eric
 * @date 2021.2.3
 */
public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {
    private static final Logger LOGGER = LoggerFactory.getLogger(JwtAuthenticationTokenFilter.class);
    @Autowired
    private UserDetailsServiceImpl userDetailsService;
    @Autowired
    private JwtTokenUtil jwtTokenUtil;
    @Value("${jwt.tokenHeader}")
    private String tokenHeader;
    @Value("${jwt.tokenPrefix}")
    private String tokenPrefix;

    @Override
    protected void doFilterInternal(HttpServletRequest request,
                                    HttpServletResponse response,
                                    FilterChain chain) throws ServletException, IOException {
        String authHeader = request.getHeader(tokenHeader);
        //如果没有携带token
        if (authHeader == null || !authHeader.startsWith(tokenPrefix)) {
            SecurityContextHolder.clearContext();
            chain.doFilter(request, response);
            return;
        }
        //获取token
        String authToken = authHeader.substring(tokenPrefix.length());
        String username = jwtTokenUtil.getUserNameFromToken(authToken);
        LOGGER.info("checking username:{}", username);
        if (username != null && SecurityContextHolder.getContext().getAuthentication() == null) {
            JwtUserDetails userDetails = userDetailsService.loadUserByUsername(username);
            if (jwtTokenUtil.validateToken(authToken, userDetails)) {
                //刷新token
                jwtTokenUtil.refreshHeadToken(tokenPrefix + authToken);
                UsernamePasswordAuthenticationToken authentication = new UsernamePasswordAuthenticationToken(userDetails, null, userDetails.getAuthorities());
                authentication.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                LOGGER.info("authenticated user:{}", username);
                SecurityContextHolder.getContext().setAuthentication(authentication);
            }
        }
        chain.doFilter(request, response);
    }
}
